Input string was not in a correct format.

We have Act Premium for Web 2006.

I can access it fine on the server.
But starting this morning when we try to login through internet explorer we get the error message:
Input string was not in a correct format.

Can anyone help?

Here is the full error page that displays:
Server Error in '/APFW' Application.
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Input string was not in a correct format.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.FormatException: Input string was not in a correct format.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.  

Stack Trace:


[FormatException: Input string was not in a correct format.]
   System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info) +0
   Act.Web.Framework.TimeZoneComparer.GetOffset(String tziName) +119
   Act.Web.Framework.TimeZoneComparer.Compare(Object x, Object y) +87
   System.SorterObjectArray.QuickSort(Int32 left, Int32 right) +93

[InvalidOperationException: Specified IComparer threw an exception.]
   System.SorterObjectArray.QuickSort(Int32 left, Int32 right) +269
   System.Array.Sort(Array keys, Array items, Int32 index, Int32 length, IComparer comparer) +372
   System.Array.Sort(Array array, IComparer comparer) +41
   Act.Web.Framework.TimeZoneManager.RebuildTimeZoneArray() +37
   Act.Web.Framework.TimeZoneManager..ctor(ACTSessionManager asm, CalendarPreferenceUtilities cpu) +58
   Act.Web.Framework.CalendarSessionInfo..ctor(HttpSessionState sessionState, ACTSessionManager sessionMgr) +162
   Act.Web.Framework.ACTSessionManager.get_CalendarInfo() +33
   Act.Web.Global.CheckForTimeZoneReminder() in C:\cvsroot\ACTForWeb\Redstone\ACT\Global.asax.cs:244
   Act.Web.Global.Global_AcquireRequestState(Object sender, EventArgs e) in C:\cvsroot\ACTForWeb\Redstone\ACT\Global.asax.cs:193
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication+IExecutionStep.Execute() +60
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +87

 


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Version Information: Microsoft .NET Framework Version:1.1.4322.2407; ASP.NET Version:1.1.4322.2407